Alcatel-Lucent says their submarine cable division Alcatel-Lucent Submarine Networks (ASN) has achieved a technological record for subsea communications by extending the reach of unrepeatered cable systems at 100 Gbps to more than 610 kilometers using the same optical fiber for both signal and amplifier transmission. Alcatel-Lucent Submarine Networks technology used a single 100 gigabit-per–second channel over a single fiber which allows for significant operational savings. Current submarine fiber optic systems have an un-repeatered distance of up to 500 kilometers.
The achievement by Alcatel will lead to significant improvements to cable system efficiency, creating benefits for operators in terms of total cost of network ownership. Mainly driven by connectivity needs, un-repeatered undersea cable projects consist in the construction of cable systems for distances currently up to 500km without using repeaters to amplify the signal. Built to offer additional capacity and/or complement terrestrial networks to gain resiliency, they can offer a design capacity of 25 Tbit/s depending on the system configuration.
Alcatel says, this technology could extend the reach of current un-repeatered systems without affecting the signal transmission and offers an optimized trade-off which significantly exceeds the capabilities of other transmission technologies, when they offer it for commercial deployment. The solution for laboratory demonstration was based on a 100 Gbps channel over a single second-generation coherent submarine fiber using advanced modulation schemes and Raman amplification.
Leveraging Alcatel-Lucent Submarine Networks’ long-standing expertise in high-performance, field-proven innovation in ultra long-distance transmission, the flexible new technology will enable deployment in multiple configurations that could further extend reach over un-repeatered distances, while ensuring ultra low-loss signal attenuation.
ASN’s un-repeatered systems support channel rates of up to 100 Gbit/s and offer a homogeneous solution for systems with a variety of segment lengths, providing cable protection and armoring options for any installation environment or sea floor conditions. ASN has deployed more than 20,000 km of un-repeatered cable systems in more than 40 projects for major telecom operators worldwide. ASN has also achieved several experiments in this domain setting world records for un-repeatered transmission distances, the latest showcasing 8 Tbit/s un-repeatered transmission of 200 Gbit/s 16 QAM channels over 363 km and 16 Tbit/s transmission of 200 Gbit/s 16 QAM channels over 321 km with third order Raman amplification in late 2014.